Although deficient face perception has been demonstrated in schizophrenia, its underlying brain mechanism and the link to social functioning remain poorly understood. Deficient affective processing of face information has been extensively studied. However, deficits in the non-affective visual and cognitive systems, which may contribute to the face perception problem, have not been systematically investigated. The overall hypotheses of this application are 1) in addition to the affective system, the compromised visual and cognitive systems that subserve the non-affective processing of face information contributes to the face perception deficit, and 2) deficient affective and non-affective facial processing is associated with social functioning to varying degrees in the schizophrenia spectrum. We will evaluate these hypotheses first by investigating the functional properties of the visual and cognitive systems specialized for processing face information in schizophrenia and schizoaffective disorder. Using psychophysical and neuroimaging approaches, we will measure the perceptual and cortical responses while patients perceive face and non-face images. These non-affective assessments will be compared with the affective assessments acquired while the patients perform emotion perception tasks. The hypotheses will be evaluated further by determining the roles of visual processing in affective processing of face information and vice versa. We will measure the effects of modulating visual features on facial emotion perception as well as the effects of modulating affective features on basic visual discrimination in patients. The investigation of the visual, cognitive and affective face processing systems will provide new insights about the nature of face perception deficits in these mental disorders. Hierarchical organization of face information highlights that deficits in each processing level, from the visual system to the face-specific system and to the affective system, contribute to face-dependent social functioning problems in schizophrenia, primarily through bottom-up mechanisms. The comprehensive assessments of the face processing systems and their relationships with daily social functioning will provide pointers to the functional domains that bottom-up process based interventions such as perceptual training of specific facial features can focus upon. PUBLIC HEALTH RELEVANCE: The goal of this study is to investigate the nature of and the brain mechanisms responsible for the face perception problem in the schizophrenia spectrum. The investigators will use state of the art psychophysical and neuroimaging approaches to evaluate perceptual and cortical responses when patients with schizophrenia or with schizoaffective disorder perform face detection, face identity discrimination and face emotion discrimination tasks. The result of this investigation will provide a knowledge basis for the development of novel interventions targeting face-related social cognitive function improvement in mental disorders.